Towards high mobility GeSn channel nMOSFETs: Improved surface passivation using novel ozone oxidation method

We present a detailed theoretical analysis to motivate GeSn for CMOS logic. High quality GeSn films have been obtained on Ge-on-Si using a CVD process. A novel surface passivation scheme is presented to achieve record low trap densities at high-κ/GeSn interface. Using the novel surface passivation method, combined with a low thermal budget device fabrication process, n-channel MOSFETs on GeSn with channel Sn content as high as 8.5% have been demonstrated for the first time.